Multiple-Input Inductor Balances Current in Power Supplies
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for balancing current drawn from multiple power supply inputs, such as resistive ballasting and active balancing, are either inefficient or complex, particularly when dealing with significantly different input voltages.
Innovation Solution
A power supply circuit utilizing multiple-input inductors and switching regulators, where dual-winding inductors are coupled between power supply inputs and switching circuits to maintain equal current draw, with the switching regulators controlled by a common switching signal to balance voltages and currents across inputs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If resistive ballasting is used to balance current from multiple power supply inputs, then current balancing is achieved, but power is wasted in the resistors especially when input voltages are significantly different
Solution Approach 1:
The patent replaces the passive resistive ballasting mechanism with an active switching regulator system controlled by a common control signal. This substitution eliminates continuous power dissipation in resistors by using switched-mode power conversion, where energy is transferred efficiently through inductors and capacitors rather than being continuously dissipated as heat in resistive elements.
Solution Approach 2:
The patent changes the operating parameters by using variable switching duty cycles for each power supply input. The control system dynamically adjusts the duty cycle of each switching regulator based on the input voltage levels, allowing efficient power transfer from inputs with significantly different voltages without the need for fixed resistive ballasting that would waste power.
2Loss of energy
If active balancing with current measurement and individual regulator adjustment is used, then efficiency is improved over resistive ballasting, but the system becomes complicated and requires a large amount of specialized circuitry
Solution Approach 1:
The patent merges the control functions of multiple individual regulators into a single unified control system. By using a common control signal that simultaneously governs multiple switching regulators, the system achieves coordinated current balancing without requiring separate control circuits, current sensing amplifiers, and microcontroller logic for each input, thereby reducing overall circuit complexity while maintaining efficiency.
Solution Approach 2:
The patent creates a universal control signal that serves multiple functions simultaneously: it controls the switching of all regulators, implicitly balances current from multiple inputs, and adapts to different input voltage conditions. This multi-functional approach eliminates the need for specialized circuitry dedicated to each individual regulation task.
3Reliability
If individual regulators with separate control are used for each power supply input, then current balancing can be achieved, but the system complexity and circuitry requirements increase
Solution Approach 1:
The patent combines multiple separate control circuits into a single common control signal source that governs all switching regulators. This unified control approach maintains current balancing capability while dramatically reducing the amount of control circuitry needed, as the same control signal performs coordination across all inputs without requiring individual control paths.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach efficiently balances current draw from multiple power supply inputs, maximizing power utilization without overloading individual inputs, even when input voltages differ significantly, and can be applied to various power supply configurations, including Power over Ethernet systems.
Implementation Method 1
a multiple-input inductor coupled between the power supply inputs and the switching circuits for balancing voltages applied to each of the switching circuits
Data Source
AI summary
Novel techniques for balancing current drawn from multiple power supply inputs. A multiple-input inductor is coupled between the power supply inputs and the switching circuits associated with the respective power supply inputs for balancing voltages applied to each of the switching circuits.